1. Field of the Invention
This invention relates to a manually displaceable implement for ground treatment, having a housing, a motor-driven rotor drum rotatably seated in the housing, a connecting piece, and height-adjustable running wheels, wherein the rotor drum is almost completely lifted off the ground to be treated in a lower end position of the running wheels.
2. Description of Prior Art
Implements for ground treatment are employed for cleaning, roughening or cutting of concrete, asphalt or metal surfaces. In general, they have a cage-like, motor-driven rotor drum as a treatment tool, with cage shafts on which several freely rotating beater disks are disposed. The rotor drum is disposed in such a way that the rotating beater disks cut down the surface of the ground to be treated. The setting of the treatment depth is performed by displacing the relative rotor drum shaft in respect to the surface of the ground. Generally this setting is performed by means of height-adjustable running wheels. The forward motion is manually generated by the person operating the implement.
In the operational state, such implements for ground treatment have the tendency to run away because of the direction of rotation of the rotor drum. Thus, the person operating the implement can expect the device to perform uncontrolled movements as soon as the motor is started. For the same reason, an implement for ground treatment, once it has been started, can no longer be released.
Some models of known implements for ground treatment are turned off when not in use by lowering the height-adjustable wheels. The rotor drum is thus lifted and the implement rests on the ground only on its wheels. The rotor drum turns freely without treating the ground. In spite of this, there is still the danger in connection with such turned-off machines that the machine moves uncontrollably forward when the motor driving the rotor is started or when the machine is parked.